RFR: 8354469: Keytool exposes the password in plain text when command is piped using | grep [v2]

[Weijun Wang]

> Add more description on password handling into the keytool man page. A link to the man page is now added to the keytool help screen.
> 
> When keytool output is redirected into a file or file, a warning is shown:
> 
> $ keytool -genkeypair | type
> 
> Warning: password will be echoed because output is redirected.
> Enter keystore password:  password
> Warning: password will be echoed because output is redirected.
> Re-enter new password:
> 
> 
> A new manual test is added.
> 
> Sorry we cannot suppress password echoing in this case at the moment because `System.console()` is not available.

Weijun Wang has updated the pull request incrementally with one additional commit since the last revision:

  hide warning when password is piped into the command; enhance test

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/24805/files
  - new: https://git.openjdk.org/jdk/pull/24805/files/591fd7f2..89ccc41d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24805&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24805&range=00-01

  Stats: 132 lines in 3 files changed: 54 ins; 52 del; 26 mod
  Patch: https://git.openjdk.org/jdk/pull/24805.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24805/head:pull/24805

PR: https://git.openjdk.org/jdk/pull/24805